What is Knockdown Disbudding?

By Bogdan Butnaru

Knockdown disbudding is now a routine procedure to prevent horn development in calves, improving safety for handlers and reducing injury risk among animals. Animals with horns can bully the others without horns, which is not permitted under Red Tractor standards. Knockdown disbudding involves sedating the calf before the procedure, simplifying handling compared to conventional disbudding. In this article we discuss why it has become popular, alongside new research about the negative effect on growth rates on sedated calves.

All disbudding has the potential to cause stress and pain. Knockdown disbudding provides several benefits:

• No set up needed: calves are restrained for a very short time only while administering the sedation. No need for a crush or any other form of handling system.
• Very efficient: The procedure is much quicker and cleaner compared to the restraint handling system

Previously, we would have assumed that knockdown disbudding reduced stress, as it requires limited handling compared to conventional disbudding, however recent research suggests that growth rates are reduced approximately 21 days post disbudding in sedated calves, compared to those conventionally disbudded. This evidence is important to discuss on farm when creating a bespoke disbudding plan for your calves.

WHAT DOES THE KNOCK DOWN PROCEDURE INVOLVE?

• Sedation: administration by a vet of a sedative to calm and relax the calf followed by lateral recumbency about 10 min later
• Pain Management: A local anaesthetic is injected halfway between the corner of the eye and base of the ear and NSAIDs for ongoing pain relief.
• Disbudding: Once the area is numb, a hot iron is used to cauterise, burn the horn bud & remove it.
• Recovery Monitoring: Calves are monitored during recovery and put in a sternal position to enable release of abomasal gases and prevent bloating. It would take 2 to 3 hours for the calves to recover fully.

HOW MUCH DOES IT COST?

There is a visit fee and a fixed charge of £9.50 per calf including sedation, pain relief and labour. While the calf is sedated, we can perform other procedures like castrations at an additional cost.

NEW RESEARCH

A recently published article found that in the shortterm post-disbudding period (up to three weeks post disbudding), sedated calves had a reduced growth rate of 0.14kg/day compared to conventionally disbudded calves. This difference was not present after 6 weeks post-disbudding, when conventionally and sedated calves growth rates were comparable.

Importantly, the level of sedation achieved had the biggest effect on this growth rate reduction, with calves who did not lie flat out after sedation, seeing the largest drop in growth rates. This cohort of calves who were incompletely sedated contributed to the overall reduction in growth rates in the sedated group.

We have worked hard within the practice to ensure that maximum sedation levels are achieved during knock down disbudding, but it is important that we monitor and discuss reasons for incomplete sedation on each farm, as breed differences and calf stress prior to disbudding may have an effect on this.

Knockdown disbudding has become increasingly popular within the practice and offers a quick and efficient method to disbud calves. However, the new research indicates that there is a short-term effect on the calves following sedation, which can result in a reduction of growth rates. If you would like more information on disbudding, please contact us for creating a disbudding plan that works for your farm.

If you would like more information on disbudding, please contact us for creating a disbudding plan that works for your farm.

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